from multiprocessing import Pool
from threading import Thread
from concurrent.futures import ThreadPoolExecutor, ProcessPoolExecutor
import time, os, math
from joblib import Parallel, delayed, parallel_backend


def f_IO(a): # IO 密集型
 time.sleep(5)

def f_compute(a): # 计算密集型
 for _ in range(int(1e7)):
  math.sin(40) + math.cos(40)
 return

def normal(sub_f):
 for i in range(6):
  sub_f(i)
 return

def joblib_process(sub_f):
 with parallel_backend("multiprocessing", n_jobs=6):
  res = Parallel()(delayed(sub_f)(j) for j in range(6))
 return


def joblib_thread(sub_f):
 with parallel_backend('threading', n_jobs=6):
  res = Parallel()(delayed(sub_f)(j) for j in range(6))
 return

def mp(sub_f):
 with Pool(processes=6) as p:
  res = p.map(sub_f, list(range(6)))
 return

def asy(sub_f):
 with Pool(processes=6) as p:
  result = []
  for j in range(6):
   a = p.apply_async(sub_f, args=(j,))
   result.append(a)
  res = [j.get() for j in result]

def thread(sub_f):
 threads = []
 for j in range(6):
  t = Thread(target=sub_f, args=(j,))
  threads.append(t)
  t.start()
 for t in threads:
  t.join()

def thread_pool(sub_f):
 with ThreadPoolExecutor(max_workers=6) as executor:
  res = [executor.submit(sub_f, j) for j in range(6)]

def process_pool(sub_f):
 with ProcessPoolExecutor(max_workers=6) as executor:
  res = executor.map(sub_f, list(range(6)))

def showtime(f, sub_f, name):
 start_time = time.time()
 f(sub_f)
 print("{} time: {:.4f}s".format(name, time.time() - start_time))

def main(sub_f):
 showtime(normal, sub_f, "normal")
 print()
 print("------ 多进程 ------")
 showtime(joblib_process, sub_f, "joblib multiprocess")
 showtime(mp, sub_f, "pool")
 showtime(asy, sub_f, "async")
 showtime(process_pool, sub_f, "process_pool")
 print()
 print("----- 多线程 -----")
 showtime(joblib_thread, sub_f, "joblib thread")
 showtime(thread, sub_f, "thread")
 showtime(thread_pool, sub_f, "thread_pool")


if __name__ == "__main__":
 print("----- 计算密集型 -----")
 sub_f = f_compute
 main(sub_f)
 print()
 print("----- IO 密集型 -----")
 sub_f = f_IO
 main(sub_f)

----- 计算密集型 -----
normal time: 15.1212s

------ 多进程 ------
joblib multiprocess time: 8.2421s
pool time: 8.5439s
async time: 8.3229s
process_pool time: 8.1722s

----- 多线程 -----
joblib thread time: 21.5191s
thread time: 21.3865s
thread_pool time: 22.5104s



----- IO 密集型 -----
normal time: 30.0305s

------ 多进程 ------
joblib multiprocess time: 5.0345s
pool time: 5.0188s
async time: 5.0256s
process_pool time: 5.0263s

----- 多线程 -----
joblib thread time: 5.0142s
thread time: 5.0055s
thread_pool time: 5.0064s